Most standard electrical heating systems usually involve using a heating element that is proximate to a material to be heated and transferring heat generated from the heating element to that material by conduction or convection. This process can be inefficient with excess heat being generated in the heating element and that heat escaping beyond the material to be heated. Also, heating elements usually need to be driven to a much higher temperature than the final desired temperature of the material. This is because a high temperature gradient is required to make the conductive or convective process work quickly. A heating element with a temperature much higher than the desired temperature for the material can be a safety problem creating the possibility for burning the user. To fix this problem the device made with a heating element usually requires the use of materials that can withstand higher temperatures and insulation incorporated into the design. This type of heating may also create non-uniform heating within the material.
Ohmic resistive heating is an alternative approach to creating a heating system. This approach involves directly passing a current through the material to be heated. This type of heating generally provides uniform heating of the material, provides more rapid heating, is more efficient and limits the maximum temperature of elements within the system. A drawback of this type of heating is that it is very dependent on the uniformity and resistive properties of the material to be heated.
Thus better types of ohmic materials are needed, as well as different device configurations to utilize these materials. The current patent application provides for a new type of ohmic material and the resulting new devices that incorporate this new material.